1. Technical Field
The invention pertains to a spring loaded nozzle arrangement for increasing the loading on the nozzle for improved cleaning performance.
2. Background Information
Upright vacuum cleaners are well known in the art. Typically, these upright vacuum cleaners include a vacuum cleaner housing pivotally mounted to a vacuum cleaner foot. The foot is formed with a nozzle opening and may include an agitator mounted therein for loosening dirt and debris from a floor surface. A motor may be mounted in either the foot or the housing for producing suction at the nozzle opening. The suction at the nozzle opening picks up the loosened dirt and debris and produces a stream of dirt-laden air which is ducted to the vacuum cleaner housing for collection and later disposal.
In conventional vacuum cleaners, the nozzle is suspended over the floor surface to be cleaned so that a pre-determined distance is maintained. Typically, the cleaner wheels are positioned so that the nozzle is supported above the floor surface the desired distance. The distance is selected so that nozzle suction is maintained on the floor surface to be cleaned while allowing air flow into the suction nozzle. Both nozzle suction and air flow into the nozzle are necessary for satisfactory cleaning efficiency. The distance the nozzle needs to be suspended over the surface to be cleaned to maintain satisfactory nozzle suction and air flow varies according to the type of carpeting and the pile height. Some cleaners allow this distance to be adjusted for varying carpet pile heights by the user moving a knob or dial on the foot of the cleaner. However, this isn""t completely satisfactory since such cleaners don""t have a setting to accommodate every carpet pile height. One setting may be too high and the next lower setting may be too low. Even when a cleaner is set to a lower setting, nozzle suction is lost because the underside of the nozzle has a tendency to be lifted from the carpet by the thicker pile. Hence, cleaning efficiency is reduced. It has been found that loading the nozzle with weight or the equivalent forces the nozzle deeper into the pile of the carpet and nozzle suction is improved. Thus, cleaning efficiency may be maintained on carpets of all pile heights.
There exists in the prior art patents for a vacuum cleaner having a spring means to urge the nozzle towards the floor surface. For example, U.S. Pat. No. 3,676,892 issued to Nordeen discloses a vacuum cleaner having an elongated floor portion propellable over a floor during cleaning and supported on the floor by a plurality of spaced front and rear wheels. A nozzle unit forms the floor portion of the cleaner and has a front suction opening end carrying a floor contacting brush and is rockable or pivotable in a vertical direction with respect to the wheels. A first spring means constantly urges the carriage downwardly at the front end to hold the brush in a cleaning position with respect to the floor regardless of the nature of the floor or its covering. A propelling handle is rockably attached to the cleaner and movable between an operating position and a storage position. A second spring means stronger than the first and operably positioned between the front wheels and the front is operably positioned between the front wheels and the front suction end of the nozzle unit. Means operated by the handle when the handle is moved to the storage position distorts the second spring means to apply an overcoming spring force to retain the nozzle unit front end away from the floor against the urging of the first spring means. The cleaner can then be operated in the customary off-the-floor cleaning of furniture, draperies and the like by the use of auxiliary equipment without permitting the brush to contact the floor.
U.S. Pat. No. 5,819,370 issued to Stein and the corresponding foreign patent publications, namely, Federal Republic of Germany Patent Application No. 195 05 106.8, filed on Feb. 16, 1995, DE-OS 195 05 106.8, and DE-PS 195 05 106.8, and European Patent Applications EP 0 727 171 A3 and EP 0 727 171 A3 describe a floorcare machine wherein the brush roller is pressed against the surface to be cleaned by a means of a spring element. The brush roller is pivotally mounted in the housing and is biased against the floor surface by means of a tension spring, or alternately, a torsional spring. The tension spring biases the roller toward the floor surface being operatively connected at the rear of the housing between the top of the housing and the inner part the roller is rollably mounted within. The torsional spring biases the roller downward toward the floor surface by being operatively mounted about the pivot the inner part is mounted onto the housing with.
However, neither of these references describe a vacuum cleaner having a means for urging the nozzle toward the surface to be cleaned and selectively allowing the user to adjust the height in which the nozzle is suspended over the floor surface. Consequently, there is a need in the art for a new and improved arrangement for loading a vacuum cleaner nozzle that also has a means to select the height which the nozzle is suspended over the carpet or surface to be cleaned while simultaneously urging the nozzle into the carpet pile regardless of the height of the carpet pile. The present invention fulfills this need by providing a vacuum cleaner having a means for adjusting the distance the nozzle is suspended over the carpet or surface to be cleaned while maintaining a biasing force on the nozzle to continuously urge the nozzle into the carpet pile regardless of the carper pile height.
Accordingly, an object of the present invention is to provide a spring loaded nozzle for a vacuum cleaner for improving cleaning performance on carpets of varying pile heights.
Another object of the present invention is to provide a spring loaded nozzle to improve nozzle suction while maintaining satisfactory air flow into the nozzle.
Yet another object of the present invention is to provide a spring loaded nozzle for suction nozzles of the fixed type.
Still yet another object of the present invention is to provide a spring loaded nozzle for suction nozzles of the floating type.
These and other objects will be readily apparent to one of skill in the art upon reviewing the following description and accompanying drawings.
In the preferred embodiment of the present invention, an upright vacuum cleaner is provided of the floating nozzle type. Such cleaners are typically comprised of an upright portion pivotally connected to a vacuum cleaner foot. The foot is generally comprised of a main body, an agitator housing pivotally connected to the main body, an agitator mounted within the agitator housing, and a hood covering the foot. The agitator housing is biased downward by a spring member such as a compression spring in operative engagement with the agitator housing to urge the nozzle towards the surface to be cleaned or the carpet pile. The vacuum cleaner may or not have a power drive unit in the foot to propel the foot over the floor surface
In an alternate preferred embodiment of the present invention, an upright vacuum cleaner is provided of the fixed nozzle type. Such cleaners are typically comprised of an upright portion pivotally connected to a vacuum cleaner foot. The foot is generally comprised of an agitator housing and an agitator mounted within the agitator housing. The vacuum cleaner may or not have a power drive unit in the foot to propel the foot over the floor surface. A least one spring member such as a coil spring or torsional spring is in operative engagement with the upper portion of the vacuum cleaner and the foot to urge the agitator housing and the nozzle towards the surface to be cleaned or the carpet pile. The vacuum cleaner may or not have a power drive unit in the foot to propel the foot over the floor surface